CVE-2017-4920 : What You Need to Know

VMware NSX-V Edge versions 6.2.x before 6.2.8 and 6.3.x before 6.3.3 are affected by a vulnerability in their OSPF protocol implementation that can lead to a denial of service attack.

Understanding CVE-2017-4920

This CVE involves a flaw in the OSPF protocol implementation in VMware NSX-V Edge versions 6.2.x and 6.3.x, potentially resulting in a loss of connectivity due to improper handling of link-state advertisements.

What is CVE-2017-4920?

The vulnerability in CVE-2017-4920 allows a malicious link-state advertisement (LSA) to exploit the system, causing a continuous exchange of LSAs between routers, which can lead to a loop or loss of connectivity.

The Impact of CVE-2017-4920

The vulnerability poses a significant risk of denial of service (DoS) attacks, potentially disrupting network operations and causing connectivity issues between routers.

Technical Details of CVE-2017-4920

VMware NSX-V Edge versions 6.2.x prior to 6.2.8 and 6.3.x prior to 6.3.3 are susceptible to the following technical details:

Vulnerability Description

The flaw in the OSPF protocol implementation allows for improper handling of LSAs, enabling a malicious LSA to trigger a never-ending exchange of LSAs between routers.

Affected Systems and Versions

Product: NSX-V Edge
Vendor: VMware
Vulnerable Versions: 6.2.x prior to 6.2.8, 6.3.x prior to 6.3.3

Exploitation Mechanism

The vulnerability can be exploited by injecting a malicious LSA into the OSPF protocol, leading to a continuous loop of LSAs between routers and potentially causing a loss of connectivity.

Mitigation and Prevention

To address CVE-2017-4920, follow these mitigation strategies:

Immediate Steps to Take

Apply the necessary patches provided by VMware to fix the vulnerability.
Monitor network traffic for any suspicious activity related to OSPF protocol.

Long-Term Security Practices

Regularly update and patch network devices to prevent vulnerabilities.
Implement network segmentation to limit the impact of potential attacks.

Patching and Updates

VMware has released patches for NSX-V Edge versions 6.2.8 and 6.3.3 to address the vulnerability.